automatic-ref-counting

问题 App crashes immediately after I attempt to login so it can’t a be a watchdog memory issue Reason: _mh_execute_header App crashes upon attempting to make a network request using ASIHTTPRequest. Request never touches server. ASIHTTPRequest: I use -fno-objc-arc to omit ASIHTTPRequest from ARC. I believe that the following call is causing my problems since my call never even touches the server when I make a request. Any help would be greatly appreciated! Call: NSDictionary *response = [

问题 This might be a silly question, but I just wanted to know. I want my code to detect if ARC is enabled, programmatically. How do I do that? Is there is any flag that I could check? Actually the problem is that, I have written an open-source library. I have used release and retain in it. if some one else uses my library files using ARC enabled, I dont want them to get any errors. how do I achieve this? or is there any possible ways I can provide any tools to compile my library before using it?

问题 An app crashes sometimes with error objc_object::release() . The Apple Developer Technical Support mentioned this: Remember that you should always do something like _tableView.delegate = nil; in your -dealloc methods, even if you are using ARC. For compatibility reasons system objects use unsafe_unretained references to implement delegation, instead of the preferred modern replacement weak . Does that mean that I have to set the delegates of system objects to nil when the view controller is

问题 I'm running the ARC conversion tool for the first time. I've followed the instructions and dealt with all of the issues/erros in my files that the conversion tool finds before it will actually run. I also have several third party libraries that I've told ARC to skip by unchecking them in the Targets to Convert dialog. After running the tool it shows me a report of all the changed files but no files have been changed. Next I save and try to build the project only to find that I have nearly

问题 dispatch_once call causes crash (in simulator) after I've converted my project to ARC. My original problem was that I've got EXC_BAD_ACCESS (in objc_retain call) crash in one of my singleton object's + (SingletonClass)shared { ... dispatch_once(..., ^{}); ... } method exactly one line before the dispatch_once call. Based on loggings, and breakpoints my code have not run into the dispatch_once call's block. I didn't know the reason, so I've just commented out the dispatch_once call. My app

问题 I want to write something like this: @interface Foo{ __strong id idArray[]; } @end But the compiler complains about it: Field has incomplete type '__strong id []'. How can I create an id array member instance under ARC? And how do I init that array? Using malloc? new[]? I don't want to use NSArray because I'm converting a large library to ARC and that will cause a lot of work. 回答1: If you want to allocate dynamically the array, use pointer type of id __strong. @interface Foo { id __strong

问题 I have an app with both ARC code and non-ARC code. The compiler will catch when I try to compile non-ARC code as ARC. How do I cause a compile time error/notice when my ARC code is erroneously compiled without ARC? Obviously, the code will compile. It will just leak. The static analyzer will catch the problem. I would rather find a way to leave a pragma or define in my ARC code. The following is defined by Apple in objc-api.h : /* OBJC_ARC_UNAVAILABLE: unavailable with -fobjc-arc */ #if

问题 Consider the following code: @interface ClassA : NSObject @property (nonatomic, copy) void(^blockCopy)(); @end @implementation ClassA @synthesize blockCopy; - (void)giveBlock:(void(^)())inBlock { blockCopy = inBlock; } @end Then use it in a class which has a strong property of type ClassA called someA : self.someA = [[ClassA alloc] init]; [self.someA giveBlock:^{ NSLog(@"self = %@", self); }]; dispatch_async(dispatch_get_main_queue(), ^{ self.someA.blockCopy(); self.someA = nil; }); If I run

问题 Problem: A library I use won't support ARC (Automatic Reference Counting). Background (for those unfamiliar to ARC): http://developer.apple.com/library/ios/#releasenotes/ObjectiveC/RN-TransitioningToARC/_index.html Manual Solution: Add the -fno-objc-arc option for each implementation file of the library, and otherwise use ARC normally in my application code. Observation: The following template file can be copied and most likely be used to either turn ARC completely ON or OFF (without adding

问题 Edit: Problem defined below actually occurred with this code: int main(int argc, const char * argv[]) { @autoreleasepool { XYZPerson *myPerson = [XYZPerson person]; myPerson = nil; NSLog(@"The end."); } } The method 'person' is a factory method. I have the following code: int main(int argc, const char * argv[]) { @autoreleasepool { XYZPerson *myPerson = [[XYZPerson alloc] init]; myPerson = nil; NSLog(@"The end."); } } XYZPerson overrides dealloc method so that it prints out something with